Four Wheel Drive Cars

Four Wheel Drive Cars

Four Wheel Drive Cars are popular the world over. For some it is an adventure but for the great part of the world 4WD cars, pick-up trucks and Sport Utility Vehicles are a necessity as there is an extreme shortage of good roads in most developing countries in Asia, Africa and Southern America.

Western is world’s top provider of 4×4 vehicles. We provide full range of four wheel drive cars from our Thailand, Singapore, Australia, United States, United Kingdom and Dubai offices. Dubai and United States offices provide new and used four wheel drive and all wheel drive cars, pick-up trucks and Sport Utility vehicles in Left Hand Drive while our Thailand, Singapore, Austraila, New Zealand and United Kingdom offices provide four wheel drive cars, pick-up trucks and sport utility vehicles SUVs in Right Hand Drive.

Difference between All wheel Drive (AWD) and Four Wheel Drive (4WD)

The term four-wheel drive can describe larger passenger vehicles that may allow the driver to manually switch (sometimes with an automatic option) between two-wheel-drive mode (if available) for streets and four-wheel-drive mode for low-traction conditions such as ice, mud, snow, or loose gravel.

All-wheel drive (AWD) can sometimes describe a “full-time” 4WD that may be used on dry pavement, but not always. These systems incorporate an inter-axle differential that allows the front and rear wheels to turn at different speeds. This eliminates driveline binding, wheel hop, and other driveline issues associated with use of 4WD on dry pavement. Because all four tires in a full-time AWD system are connected by a system of differentials, the type of differential(s) can have a significant impact on the behavior of the system under low-traction conditions. For example, if the system utilizes standard “open” differentials (this is, a standard geared differential with no mechanism to limit speed and/or torque difference between outputs), the loss of traction of one wheel will result in all of the drive power being “sent” to that wheel, and thus a loss of forward tractive effort. For this reason, most AWD systems are comprised partially or wholly of “limited slip” type differentials, which utilize one of a variety of methods to limit the speed/torque difference between outputs. One common configuration is to use a LSD in the “center” of the vehicle, with standard open differentials at the front a rear, thus ensuring that, at a minimum, one front and one rear are provided with torque. Another common configuration is to use a LSD in the center and rear of the vehicle. It follows that the most effective arrangement (in terms of traction), but also most expensive and complex, is to use a limited slip differential in the center, front, and rear locations. This configuration provides a very high level of traction, even on slippery surfaces.

Advantages

Part-time 4WD systems are mechanically simpler and cheaper than AWD systems. Also, a part-time 4WD transfer case is usually equipped with a reduction gear setting, or, low range, which provides for higher torque at lower speeds, a vital feature for vehicles that see much off-road use. In AWD systems a more expensive separate reduction gearbox is usually used. The main drawback of 4WD is that because it lacks a center differential, a part-time 4WD system can only be used in low traction situations where the wheels have the ability to slip as needed.

For these reasons, full-time AWD is appropriate for improving on-road handling and is seen on cars and crossover/sports utility vehicles, while traditional part-time 4WD systems without center differentials, or with locking center differentials, are better for heavy-duty use such as off-road or in deep snow and are commonly seen on trucks and truck-based SUVs.